【作者】 雷晓东；

【导师】 熊蓉春；

【作者基本信息】 北京化工大学 ， 应用化学， 2002， 硕士

【摘要】 以异丙醇铝为原料,采用溶胶-凝胶法制备了γ-Al2O3陶瓷NF膜。分析了加水量、酸用量、反应温度和时间对伯姆石(AlOOH)溶胶稳定性的影响,讨论了涂膜过程、凝胶干燥过程、焙烧过程以及成膜助剂对获得高质量的γ-Al2O3NF膜的影响。通过N2吸脱附测试表征得出,在优化条件下制得的γ-Al2O3膜的BJH脱附平均孔径为3.9nm,孔径分布非常窄,BET比表面积为245m2/g,BJH脱附累积孔容为0.33cm3/g,为高质量的γ-Al2O3 NF 膜。酸碱腐蚀测试表明,膜片在pH>1的盐酸溶液中和pH<13的氢氧化钠溶液中稳定。本工作采用适当的成膜助剂和程序升温,结合截留率-厚度梯度曲线法实现了膜厚和膜孔径及孔径分布的优化控制。首次研究了陶瓷NF膜对Ca2+的工作曲线。采用自制的γ-Al2O3陶瓷 NF膜处理CaCl2溶液,Ca2+的截留率在等电点(pH=7.5)时最低;随着CaCl2浓度的上升,Ca2+的截留率下降;随着压力的上升,Ca2+的截留率随之上升;在同一压力下,Ca2+的截留率略高于Mg2+的截留率。首次采用陶瓷NF膜处理了青霉素制药污水。在跨膜压差为0.5MPa时,自制的γ-Al2O3 NF膜对该污水的硬度、硫酸盐和色度的脱除率分别为55.5%、52.1%和83.0%,而且对异味的脱除率较高;膜的通量为21.76L/m2·h。更多还原

【Abstract】 The γ-Al2O3 NF membranes were produced by sol-gel technique using aluminium iso-propoxide as precursor. The effect of quantity of water and peptizing acids, temperature and time of reaction on the stability of boehmite sol (AlOOH) was analyzed. The influence of filming, gel drying and calcinating processes and template agent on the preparation of γ-Al2O3 NF membrane with excellent quality was discussed in detail.The structure ofγ-Al2O3 NF membranes were studied by N2 absorption and desorption test. The BJH desorption average pore diameter, BJH desorption cumulative volume of pores and BET surface area of these obtained membranes under the optimized experimental conditions were about 3.9nm, 0.33cm3/g and 245m2/g respectively, and the pore size distribution was very narrow. So, the membranes areγ-Al2O3 NF membranes with high quality. It is shown that the membrane sheets were corroded in hydrochloric acid solution with pH=1 and sodium hydroxide solution with pH=13. In this work, membrane thickness and pore size and its distribution were controlled effectively by using certain template agent, temperature programming and retention VS thickness gradient curve method.The retention property ofγ-Al2O3 NF membrane for Ca2+ was studied firstly. The quite special curve was obtained by studying the relationship between Ca2+ retention and the pH of solution treated: when the pH of solution treated is 7.5, there is minimal Ca2+ retention. The experimental results show that Ca2+ retention decreased with the increasing of feed concentration, and with the increasing of trans-membrane differential pressure, the Ca2+ retention increased, water volume flux increased linearly and the retention of Ca2+ is more than that of Mg2+ at same pressure. In this study, penicillin pharmaceutical wastewater was treated by ceramic NF membrane firstly. When pressure is 0.5MPa, with obtained γ-Al2O3 NF membrane, the retentions of hardness, sulfate and chroma were 55.5%, 52.1% and 83.0% respectively, and the retention of foreign taste is very high. The flux of membrane is 21.76L/m2·h。更多还原